Wind turbine lightning protection system

Patent metadata

Field	Value
Publication number	US-2023272780-A1
Application number	US-202118006915-A
Country	US
Kind code	A1
Filing date	Jul 26, 2021
Priority date	Jul 27, 2020
Publication date	Aug 31, 2023
Grant date	—

Abstract

A wind turbine blade comprising a lightning protection system, which is at least partly disposed in an inboard portion of the blade. The lightning protection system comprises a down conductor cable portion and a supporting component to hold the cable portion in free space in a position near or on a camber line of the blade aerofoil section, so that the cable portion is spaced apart from at least one electrically conductive structural component. The lightning protection system may comprise a plurality of inboard down conductor cables and a diverging electrical junction; and/or a down conductor cable having root and tip portions having insulation with different electrical breakdown voltages.

First claim

1 . A wind turbine blade comprising:
a root end and a tip end, a spanwise dimension extending between the root and tip ends; and an inboard portion extending up to 50% of the spanwise dimension from the root end towards a midpoint between the root and tip ends; at least one electrically conductive component disposed in the inboard portion; and a lightning protection system comprising:
a down conductor cable portion, disposed inside the inboard portion of the blade; and
a supporting component,
wherein the down conductor cable portion is secured in free space by the supporting component in a position near or on the camber line of the blade aerofoil section, spaced away from the at least one electrically conductive component.

2 . The wind turbine blade of claim 1 , wherein the at least one electrically conductive component is a structural component comprising a spar cap, optionally wherein the spar cap comprises carbon fibres, optionally wherein the carbon fibres are pultruded carbon fibres.

3 . The wind turbine blade of claim 1 , wherein the blade comprises two shell halves, each shell half having an electrically conductive component, and wherein the down conductor cable portion is spaced substantially equally from both electrically conductive components.

4 . The wind turbine blade of claim 1 , wherein the blade comprises at least one shear web, and the down conductor cable portion is secured in free space by the supporting component, spaced away from the at least one shear web.

5 . The wind turbine blade of claim 4 , wherein the supporting component is attached to the at least one shear web.

6 . The wind turbine blade of claim 5 , wherein the supporting component is attached to the at least one shear web at least two locations on the shear web.

7 . The wind turbine blade of claim 5 , wherein the blade comprises at least two shear webs, and the supporting component is attached to more than one of the at least two shear webs.

8 . The wind turbine blade of claim 7 , wherein the down conductor cable portion is disposed substantially centrally between a pair of the at least two shear webs.

9 . The wind turbine blade of claim 1 , wherein the supporting component is one or more of: a foam piece; a foam sack; a bracket, optionally an X-shaped bracket, a C-shaped bracket, a Y-shaped bracket; or a straight beam.

10 . The wind turbine blade of claim 1 , wherein the down conductor cable portion at least partly overlaps with the electrically conductive component in a spanwise direction.

11 . The wind turbine blade of claim 1 , wherein the lightning protection system further comprises:
a down conductor; a diverging electrical junction disposed in the inboard portion; and a plurality of inboard down conductor cables arranged electrically in parallel to one another, disposed in the inboard portion; wherein the lightning protection system is configured so as to conduct electricity through the down conductor, through the diverging electrical junction, through the plurality of inboard down conductor cables, towards the root end of the blade.

12 . The wind turbine blade of claim 11 , wherein the down conductor cable portion is at least a portion of any of the plurality of inboard down conductor cables.

13 . The wind turbine blade of claim 1 , wherein the lightning protection system further comprises:
a down conductor cable having the down conductor cable portion; wherein the down conductor cable further comprises a cable first portion and a cable second portion, the cable first portion being closer to the root end of the blade than the cable second portion, each cable portion comprising insulation which has a respective electrical breakdown voltage, wherein the cable first portion insulation electrical breakdown voltage is higher than the cable second portion insulation electrical breakdown voltage.

14 . The wind turbine blade of claim 13 , wherein the down conductor cable portion comprises the cable first portion and/or the cable second portion.

15 . The wind turbine blade of claim 1 , wherein at least one of the down conductor cables or the down conductor cable portion is spaced apart from an electrically conductive portion of one or more of; a sensor system; a de-icing system, an anti-icing system; a lighting system; a load control system.

16 . The wind turbine blade of claim 1 , wherein the inboard portion extends up to 40% of the spanwise dimension from the root end towards the tip end.

17 . The wind turbine blade of claim 1 , wherein the inboard portion extends up to 30% of the spanwise dimension from the root end towards the tip end.

Assignees

• Vestas Wind Sys As

Inventors

• Brilliant Nathan A
• Lykkegaard Lasse
• Thwaites Angela

Classifications

• F03D1/0684

  Shear webs · CPC title

• F03D80/301

  Lightning receptor and down conductor systems in or on blades · CPC title

• F03D1/0675 Primary

  of the blades · CPC title

• F03D80/30 Primary

  Lightning protection · CPC title

• H02G13/80

  Discharge by conduction or dissipation, e.g. rods, arresters, spark gaps · CPC title